JP05-246256A discloses a riding mower provided with an engine mounted to a rear part of a mower body, an operator's seat arranged at a location immediately front of the engine, a battery arranged in a space below the operator's seat, and a fuel tank. In this riding mower, since the heavy battery and fuel tank are arranged below the operator's seat, a rearward shift of the center of gravity due to the engine mounted in the rear part is resolved and, thereby improving the weight balance of the entire mower body. However, since the space below the operator's seat is limited, a large-capacity fuel tank cannot be arranged. If the large-capacity fuel tank is arranged forcibly, it may cause another problem that the operator's seat is located high.
U.S. Pat. No. 5,347,799 discloses a riding mower in which an engine, a fuel tank, and an air cleaner are arranged in a horizontal plane behind an operator's seat. In this case, the fuel tank is located lateral to the engine, and the air cleaner is located behind the fuel tank. Since the fuel tank, the operator's seat, the engine, and the air cleaner are arranged without overlapping with each other when seen from above of the riding mower, it becomes possible to suppress the height of the riding mower. However, the capacity of the fuel tank becomes smaller, resulting in more frequent refueling.